Signal down conversion, particularly in the K and mm wave bands, is important in high bandwidth communication systems. Electronic down conversion is susceptible to signal loss and distortion. Long distance transmission of such electronic signals is also susceptible to electro-magnetic interference.
Optical radio-frequency (RF) carrier generation is useful for ultra-high-frequency operations as well as optically feeding the RF signal to a remote antenna site, with benefits in weight reduction as well as electro-magnetic interference immunity. However, no system or methodology exists to implement signal down conversion with optical carriers to create a local oscillator.
It would be advantageous to generate optical RF carriers with amplitude and phase-modulation to enable high-order quadrature amplitude modulation with the possibility of optically remoting the modulated signal.